Beer container

ABSTRACT

A beer container comprises an inner hollow shell of blow moulded PET to hold beer, an outer hollow shell of moulded high density polyethylene enclosing and supporting the inner shell and a spear structure including a dispenser tube extending from a bottom interior region of the inner shell through to a dispensing outlet at the top of the outer shell. The spear structure incorporates valves for supply of pressurizing gas into the interior of inner shell and for dispensing beer through the dispensing outlet, both valves being formed of PET. When the container has been emptied of beer, the outer shell can readily be separated from the inner shell and spear structure to allow separate recycling of the high density polyethylene material and the PET material.

TECHNICAL FIELD

This invention relates to beer containers and particularly to containersfor rapidly dispensing beer in commercial establishments or at sportingand social events.

BACKGROUND OF THE INVENTION

Beer is presently supplied to commercial establishments or for specialevents in stainless steel kegs. These are of sturdy welded stainlesssteel construction and are fitted with a dispensing spear structurecomprising a long stainless steel dispenser tube through which todispense beer from the bottom of the keg and a pressurising valvethrough which to supply pressurising CO₂ gas into the keg so as topressurise the contents and force the beer out through the dispensingtube when a dispensing valve is operated.

Stainless steel beer kegs are very expensive to produce and they aredesigned to be returned to the brewery for cleaning and refilling. Theywill typically be the property of the brewery which may accordingly needto have large sums of capital committed to maintaining appropriatestocks of kegs. Large sums can be lost if kegs are not returned. Thisproblem could be largely overcome if it were possible to supply beer inbulk in low cost disposable dispensing containers, but no satisfactorycontainers for this purpose have hitherto been available.

Plastics technology has been applied to the manufacture of disposablebeverage containers in small sizes, such as soft drink and beer bottles.These have generally been blow moulded in PET (polyethyleneterephthalate), but it has not been possible to apply this technology tothe production of larger size dispensing containers because of thebarrier properties of PET in large size containers and the problem ofproducing a construction which allows effective recycling of all of thematerials required for the dispensing components of a workablecontainer. The present invention overcomes these problems by providing amulti-component container in which all components may be fullyrecyclable.

DISCLOSURE OF THE INVENTION

According to the invention, there is provided a beer containercomprising:

an inner hollow shell of blow moulded PET to hold beer;

an outer hollow shell of moulded high density polyethylene closing andsupporting the inner shell; and

a spear structure including a dispenser tube extending from a bottominterior region of the inner shell through to a dispensing outlet at thetop of the outer shell.

Preferably, the spear structure in fixed to the inner shell and isconstructed of PET.

The spear structure may incorporate a valve for supply of pressurisingCO₂ gas into the interior of the inner shell and a beer dispenser valveAt the dispensing outlet, both valves being moulded in PET.

Preferably, the outer shell is formed in separable pieces which can beseparated from the inner shell for recycling of the high densitypolyethylene of the outer shell separately from the PET material of theinner shell and the spear.

The outer shell may, for example, be comprised of a generally opentopped tub-shaped body fitted with a releasable lid. The lid may be asnap fit on the tub shaped body.

Preferably, the inner shell is a sliding fit within the tub shaped mainbody of the outer shell, whereby it can be slid from the outer shellmain body when the lid is removed.

The peripheral wall of the outer shell may be formed with a series ofcircumferentially spaced, inwardly projecting ribs to engage the innershell at circumferentially spaced locations to provide the sliding fitof the inner shell within the outer shell.

Alternatively, the outer shell may have a plain cylindrical peripheralsurface within which the outer shell is a neat sliding fit.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be more fully explained, one particularembodiment will be described with reference to the accompanyingdrawings, in which:

FIG. 1 is a perspective view of a beer keg constructed in accordancewith the invention;

FIG. 2 is a vertical cross section through the beer keg of FIG. 1; and

FIG. 3 is an enlarged detail of an upper part of a spear structureinstalled in the keg.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The illustrated beer keg comprises an inner hollow shell 11, an outerhollow shell 12 enclosing and supporting the inner shell, and a spearstructure denoted generally as 13. Spear structure 13 comprises adispenser tube 14 extending from an inlet opening 15 near the bottom ofthe inner shell 11 to a dispensing outlet 16 located at the top of theouter shell 12.

Inner shell 11 serves as a receptacle to be filled with beer. It has agenerally cylindrical mid-part 11A, an upwardly domed upper-part 11B,and a downwardly domed lower part 11C which form a hollow containerapproximating a prolate spheroid. The inner shell also has a cylindricalneck part 11D standing up from the domed upper part 11B and surroundingan upper-part of the spear structure 13.

Inner shell 11 is blow moulded from PET. In cases where short shelf lifeis not a problem, it may be moulded in a single layer of PET. In orderto improve shelf life by limiting ingress of oxygen and egress of CO₂,the shell 11 may be blow moulded with a multi layer or laminatedconstruction as is known in the production of PET bottles, oralternatively, it may be lined internally with an inert coating to serveas a barrier to permeation by oxygen and CO₂ or a barrier coating may besprayed on and may be such that it can be washed to allow recycling ofthe PET material of the inner shell. Suitable barrier coatings for thispurpose are disclosed in International Patent Application PCT/US95/01545of PPG Industries Inc., published Oct. 12, 1995, under No. WO 95/26997,the disclosure of which is hereby incorporated by reference herein.

Spear structure 13 is formed of moulded PET components and it is fixedinto the upper end of the inner shell 11 by heat swaging the neck part11D of the inner shell onto upper part of the spear structure so thatthe inner shell 11 and spear structure 13 form a unitary structureconsisting essentially of PET, but optionally with a barrier coatingwhich can be washed off before recycling of the PET material.

Outer shell 12 is formed of components, both moulded of high densitypolyethylene, namely an open topped tub shaped main body part 17 and anupper lid part 18 which is a press fit into the main body part. Theperipheral wall of the main body part 17 is formed with twocircumferential outstanding ribs 19 which aid in handling of thecontainer with mechanical handling equipment. Indeed the outer shell orcontainer may have the same external dimensions and features asconventional stainless steel kegs to enable the container to begenerally handled and filled with the same equipment as the standardstainless steel kegs.

Inner shell 11 serves as a hollow beer container which is fitted withina hollow enclosure 21 formed by the tub shaped main body part 17 and lidpart 18 of the outer shell 12. The cylindrical mid-part 11A of the innershell is a sliding fit within the tub shaped main body part 17 of theouter shell. The lower end of the outer shell is shaped to form anupwardly dished floor 22 for the enclosure 21, with a curvature to matchthe domed lower part 11C of the inner shell thereby to provide secureand effective bottom support for the inner shell. The lower end of theouter shell is also shaped to form a peripheral base rim 20 disposedabout the floor 22 and extending below the floor to flat base surfaces20A to provide a stable base on which the keg can be stood upright.

Upper lid part 18 is upwardly dished to receive the domed upper part 11Bof the inner shell, thereby to provide firm location of the upper partof that shell. Lid part 18 has a central opening 23 through which thetubular nick 11D of the inner shell and the upper part of open structure13 project for a short distance. Lid part 18 also has an outerperipheral flange 24 which is a press fit within the main body part 17of the outer shell at a location below its upper end, the upper end ofpart 17 thus forming an upstanding peripheral skirt 24 of the outershell 12 which extends around and protects the projecting upper part ofthe spear structure 13.

The upper part of spear structure 13 includes a moulded PET valve body25 which is fitted to the upper end of dispensing tube 14 and has acentral tubular spigot 26 defining the dispensing opening 16. Valve body25 has an outer tubular barrel part 27 surrounding the spigot 26 andincorporating at its upper end an annular coupler 28 to couple the spearstructure to a beer dispensing system as described below. The spearstructure 13 is fixed to the inner shell 11 by heat swaging the tubularneck 11D of the shell about the upper part of the outer barrel part 27of the spear valve body 25, an O-ring 29 being clinched between thevalve body and the neck 11D to form a gas tight seal to prevent escapeof gas from the inner shell when it is pressurized.

A series of circumferentially spaced annular passages 31 are formed invalve body 25 between the central spigot 26 and outer barrel part 27 andthe lower ends of these passages are closed by an annular sealing ring32 snap fitted into a circumferential recess in the lower part of valvebody 25 to serve as a one way valve for flow of CO₂ gas downwardly intothe inner shell through the passages 31. A spool valve 33 fitted with anO-ring seal 34 is located within the central spigot 26 of valve body 25to close the dispensing opening 16 unless depressed downwardly againstthe internal gas pressure,

Pressuring CO₂ is applied to the interior of the inner shell 11 throughthe valve passages 31 and outer valve 32 which acts as a one-way valveto hold the pressure within the container, the spool valve acting underthe internal pressure to close off the dispensing opening 16. Todispense beer from the pressurised container a conventional dispenser iscoupled to the upper end of the spear structure by means of the coupler28, the dispenser incorporating a mechanically operable plunger todepress the inner valve spool 33 to allow beer to flow through thedispensing opening 16 into the dispenser.

When inner shell 11 is charged with beer and is pressurised, it isexpanded firmly against the outer shell 17 so as to be firmly locatedand supported. When the container has been emptied of beer, the lid 18of outer shell 12 can be readily removed to allow the inner shell 11(and with it the spear structure 13) to be removed from the main bodypart 17 of the outer shell. The unpressurised inner shell 11 is asliding fit within the outer shell and it is readily removable. The twoparts of the outer shell can be directed to a recycling plant forrecycling of high density polyethylene material. The inner shell 11 andspear structure 13 can be directed to a plant for recycling PETmaterial, such plant including a wash to wash out any gas barriercoating applied to the inner shell.

The illustrated beer keg construction can be produced quite economicallyas a fully disposable, low cost containers Moreover, it is fullyrecyclable since it can be readily separated into PET and high densitypolyethylene components which can be fed to existing recyclingfacilities for those particular materials. However, the illustrated keghas been advanced by way of example only and the invention is notlimited to the details of that construction. Containers according to theinvention may be produced in a variety of sizes and the constructionaldetails may vary according to the particular size of the container. Forsome sizes, for example, the main body part of the outer shell may beformed with circumferentially spaced reinforcing ribs projectinginwardly of the shell and providing circumferentially spaced supportsfor the inner shell rather than continuous support about the peripheryof the inner shell. The spear construction could also be variedconsiderably for differing size containers. It is accordingly to beunderstood that the invention is no way limited to the constructionaldetails of the illustrated beer keg and that many modifications andvariations will fall within the scope of the appended claims.

What is claimed is:
 1. A beer container comprising: an inner hollowshell of blow moulded PET to hold beer; an outer hollow shell of mouldedhigh density polyethylene enclosing and providing side, top and bottomsupport for the inner shell; and a spear structure fixed to the innershell and including a dispenser tube extending from a bottom interiorregion of the inner shell through to a dispensing outlet at the top ofthe outer shell, a valve for supply of pressurising gas into theinterior of the inner shell and a beer dispenser valve at the dispensingoutlet.
 2. A beer container as claimed in claim 1, wherein the spearstructure including the valve for supply of pressurising gas and thebeer dispensing valve is constructed of PET.
 3. A beer container asclaimed in claim 1, wherein the inner shell has an upwardly projectingtubular neck which surrounds an upper part of the spear structure.
 4. Abeer container as claimed in claim 3, wherein the neck of the innershell projects through an opening in the outer shell.
 5. A beercontainer as claimed in claim 1, wherein the outer shell has anupstanding peripheral skirt projecting upwardly about the upper part ofthe spear structure.
 6. A beer container as claimed in claim 1, whereinthe lower part of the outer shell forms an upwardly dished floor supportfor the inner shell.
 7. A beer container as claimed in claim 6, whereinthe lower part of the inner shell is downwardly domed to match thedished floor support.
 8. A beer container as claimed in claim 6, whereinthe lower part of the outer shell also forms a peripheral base rimdisposed about the dished floor support and extending below that floorsupport to provide a base on which the container can be stood upright.9. A beer container comprising: an inner hollow shell of blow mouldedPET to hold beer; an outer hollow shell of moulded high densitypolyethylene enclosing and supporting the inner shell; and a spearstructure constructed of PET and fixed to the inner shell, the spearstructure including a dispenser tube extending from a bottom interiorregion of the inner shell through to a dispensing outlet at the top ofthe outer shell.
 10. A beer container as claimed in claim 9, wherein theouter shell is formed in separable pieces which can be separated fromthe inner shell for recycling of the high density polyethylene of theouter shell separately from the PET material of the inner shell and thespear.
 11. A beer container comprising: an inner hollow shell of blowmoulded PET to hold beer; an outer hollow shell of moulded high densitypolyethylene enclosing and supporting the inner shell; and a spearstructure constructed of PET including a dispenser tube extending from abottom interior region of the inner shell through to a dispensing outletat the top of the outer shell, wherein the outer shell is formed inseparable pieces which can be separated from the inner shell forrecycling of the high density polyethylene of the outer shell separatelyfrom the PET material of the inner shell and the spear, the outer shellcomprising a generally open topped tub-shaped body fitted with areleasable lid.
 12. A beer container as claimed in claim 11, wherein thelid is press fit on the tub shaped body.
 13. A beer container as claimedin claim 11, wherein the inner shell is a sliding fit within the tubshaped main body of the outer shell, whereby it can be slid from theouter shell main body when the lid is removed.
 14. A beer container asclaimed in claim 13, wherein the inner shell has a cylindricalperipheral surface with which the outer shell is a neat sliding fit.